// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/pending_task.h"

#include "base/tracked_objects.h"

namespace base {

PendingTask::PendingTask(const tracked_objects::Location& posted_from,
    /*OnceClosure*/ Closure task)
    : base::TrackingInfo(posted_from, TimeTicks())
    , task(std::move(task))
    , posted_from(posted_from)
    , sequence_num(0)
    , nestable(true)
    , is_high_res(false)
{
}

PendingTask::PendingTask(const tracked_objects::Location& posted_from,
    /*OnceClosure*/ Closure task,
    TimeTicks delayed_run_time,
    bool nestable)
    : base::TrackingInfo(posted_from, delayed_run_time)
    , task(std::move(task))
    , posted_from(posted_from)
    , sequence_num(0)
    , nestable(nestable)
    , is_high_res(false)
{
}

PendingTask::PendingTask(PendingTask&& other) = default;

PendingTask::PendingTask(const PendingTask& other) = default;

PendingTask::~PendingTask()
{
}

PendingTask& PendingTask::operator=(PendingTask&& other) = default;

bool PendingTask::operator<(const PendingTask& other) const
{
    // Since the top of a priority queue is defined as the "greatest" element, we
    // need to invert the comparison here.  We want the smaller time to be at the
    // top of the heap.

    if (delayed_run_time < other.delayed_run_time)
        return false;

    if (delayed_run_time > other.delayed_run_time)
        return true;

    // If the times happen to match, then we use the sequence number to decide.
    // Compare the difference to support integer roll-over.
    return (sequence_num - other.sequence_num) > 0;
}

} // namespace base
